Regenerative open-hearth furnace.



T. B. ROGERSGN.

RRGENERATIVE OPEN HEARTH FURNAGE.

APPLICATION FILED PEB.24,1914.

www@ July 21, 1914E m n. w. l

paired. it is heated up again and can therenineties.

THOMAS BOND ROGERSON, 0l? TQLLCRGSS, GLASGOV, SCOTLAND.

REG-ENERATKVE OPEN-HEARTH FURNACE.

To all whom t may concern.

Be 1t known that I, Ti-ionlis Bonn RoannsoN, a subject of the King ot Great Britain,

residing at Tollcross, Glasgow, Scotland,

have invented certain new and useful linprovements Relating to RegenerativeOpen- Hearth Furnaces, of which the following is a specification.

his invention relates open hearth furnaces.

At present, with such furnaces, when what isv technically termed the t block (t. c. the Wall or arch of refractory material having vthe air and ras ports therein) is burnt. or gives ivay, it is usual to take the gas oli/'lie furnaee'and allow the furnace to coo dovvn and thereafter rebuild the block .with bricks. This procedure takes some. time, Amuch as from four days to a Week according to the type of furnace, so that, during tlvis period, the .furnace is not Working, Whic'imeans a very considerable pecuniary loss. After the furnace has been reto regenerative after be used as before. The cooling down and reheating of the furnaeewand checker Work is injurious te and tends to sho] ten the life thereof.

Many devices have been suggested or devised with the object of lengthening the useful life of the block but all are'costly,

-rnany are cumbrous, and others again require constant upkeep. A method adopted is, at conside 'able expense, to build the block very massively so as to prolong the leffective workability of the furnace while, in some instances, for this object, hollow castings, through which Water can circulate, are built in the brickwork. in other cases again the Whole block is made removable so that, when burnt, or remlered ineffective, it can be lifted out by a crane and then be replaced by :mother block which is lowered into position. Owing' to the trouble and expense connected with such methods they have not heretofme been generally adopted. `instead of adoptingv such methods of overcoming' the difficultyl/have devised an entirely new inethod whereby the burned block can be rcpaircd andlcngthened to the desired extent in a very short interval of time, say a. few hours, and,y what is of very great importance. this 'epair can be effected without interrupting'fthe operation of the furnace, so of heat durino the repair, no loss of output that there is no loss, or practically no loss,

Specification of 4Letters; Patent.

Patented July 2i, ihre.

pplcation filed February 24, 19kt. Serial No. 820,381.

and no cooling' and re-heating of the furnace and checker work; further, the repair can be eilccted without interferingr with the working parts of the furnace. The method adoptml is simple and its cost is negligible, all the materials used being easily obtained at a louv cost, and the repair work can be effected by the Workmen themselves. l be lieve l am the first to devise a method whereby a burned-out block can be repaired during' the working of the furnace and Without the necessity for interrupting the operation of the furnace or interfcringwith its Woirking` parts. i

The essential feature of the invention is that, while the furnace is working, a cen-- ter as l term it, is inserted in position in the block`I and then refractory material in a suitable plastic condition is placed or piled on or about' the center so as to repair the burned part, the plastic material quickly hardening under the aetionvof the heat. i

I have shown on the .lraivingrs annexed, and by way of example, a mode of carrying out the invention in connection with a Siemcns open hearth furnace.

Figure 1 is a vertical section of the open hearth furnace. Fig. 2 is a cross section taken on the line X, X, Fig. l. Figs. 3 and l show means which l may use when repair inga block.

Un the d rawing's, o represents the furnace,

7; a working door, c the .Workingl bed or hearth, Z the air port, c, e, gas ports, f the slag,` pocket, and 57 a gas regenerating chamber.

Under my invention, when the block z', between the air port and a ,f as port (or ports) is burnt or rives way to such an extent as to render it necessary to repair the same, l insert, in the gas port (or ports)v while the furnace is working, what l call a center,"1 this center being'.y preferably, more or less arched or tubular in shape. The center is pushed' or otherwise inserted into the port (or ports). In the case of the ccn- `ter shown in lfigr. l. it is pushed into the gras port from the back, a. hole being provided at y' for the purpose, and which is normally closed with bricks or other stopping.

ll/Then the center is in place. it is easy for the workmen, by operating suitable working tools through the adjacent working` door and the back opening;- j, to 'rebuild the block l'iypiling;` on vnd about the center a mixture made plastic ny the addition of Water and one hour. I have found, in practice, that a.

41l0'mixture consisting,A by measure, of 50%l face finish.

consisting of broken silica brick, silver sand,

l and a silica clay, or other suitable refractory mixture, this being done while the furnace is working. The mixture soon hardens under the great heatl while the center itself may burn away and leave the newly formed part of the block in position. In practice, I have effected a comp ete repair operation in about 'measure After the mixture has been acted v.upon by the `gas for about half an hourv or so a little brown sand may be thrown on the rebuilt block so as to give a glazed sur- In Fig. 1 the full lines 'show4 the block as originally built, the dotted line at t shows the distance to whiclrthegblock may have been burnt away and the cross dotted lines at 2 show the rebuilt part of the block/,supported on the center h. The center may be made of metal or refractory material and y may conform in section, more or less, to the shape of the port but vbe somewhat smaller' so as to readily slip thereinto. I find, in practice, that a plate h1 of sheet iron or steel rolled to the shape shown at Figs. 3 and 4 is very suitable as it can be easily slid into place in the `gas port. A reclay pipe ora cast or wrought iron or steel tube of suitable` length and4 shape-would b'e equally suitable for 4the purpose, the object being simply. to provide. means sufficiently strong and ireresisting to hold the plastic mixture in position until it hardens. y

I have described the invention merely by way of illustration .or example, as employed in connection with one type of regenerative open hearth furnace havingv a single air "port and two gas ports but it is, of course,

to be understood that it can be employed in connection withl furnaces having two o1 more air ports and two or more gas ports,

If two or more gas ports are burnt away then two or more centers may be used and the block re-built in the same manner as for a single port Having now fully described my'invention,

what I claim and desire to secure by Letters Patent is 1. The method'of repairing the burnt blocks of regenerative open hearth furnaces by first inserting, in the block, a center and p a'c'ing same in position where the portion of the block has been destroyed, and then applying refractory material about the ce n ter to replace the portion destroyed.

2. The .method ofrepairing the burnt blocks of regenerative open hearth furnaces by providing an opening inthe furnace. in. serting a center through said` opening and into position at theA place where the block hasbeen destroyed, placing a refractory material aboutr the center `to replace the portion destroyed and thereafter closing the opening in the furnace. I

3. Repairing the burnt blocks of regenerative open hearth furnaces by first inserting, in the block, a center and placing same in position where the portion of the block has been destroyed, and then applying a refractory mixture, composed of broken silica. brick, silver sand and'clay, about the center to replace the portion destroyed.

4.' Repairing 'the burnt blocks of regenerative open hearth furnaces by first inserting, 1n the block, a center and placing` same in positionvwh'ere the portion of'the block has been destroyed, then applying a mixture of refractory material,l composed broken asilica brick, silver sand and silica/ clay, about the center to replace the portiondestroyed, and finishing off the rebuilt block with a mixture composed of silver sand and silica clay, brown sand being nally thrown on therebuilt block for the purpose of glazing the same.

5. The inode of repairing the burnt blocks l of regenerative open hearth 'furnaces by first inserting, in the block,` a center, consisting'of a curved plate of sheet metal, and placing same in position where the portion of the block has been destroyed, and then apply inga mixture of refractory material about the center to replace the portion destroyed.

G. rl`he method of repairing the burnt blocks of regenerative open hearth furnaces by first inserting, in the block,.a center and placing` same in position where the portion of the block has beenl destroyed, and then ap.- plying refractory material, in a plastic con dition, about the center to replace the portion destroyed.

In testimony whereof aiiix my signature in presence of two witnesses.

THOMAS Bonn noennsou. 

